Study On The Correlation Between Uric Acid, Adiponectin And Vasculial Endothelial Function

Objective:1) To investigate how to establish a chronic, relatively stable and lasting rat model of hyperuricemia (HUA).2) To reveal the relationship between the change of serum uric acid (SUA), adiponectin (APN) in hyeruricemia rats and vascular endothelial function, and provide the basis for early interventions for clinical hyperuricemia. Methods:1) 36 male SD rats were randomly divided into normal control group, model group and the allopurinol treatment group,12 in each group.Normal control group were given a normal sodium lavage and peritoneal injection.To induce hyperuricemia, model group were given the high yeast diet (20% yeast extract +80% diet) united the peritoneal injection of suspension of potassium oxonate (30mg/ml) dailly.Besides the same disposal in model group, allopurinol treatment group were givine a suspension of allopurinol (10mg/ml) at the same time. The experiment lasted for 6 weeks.2) Systolic blood pressure was messured regularly. Serum uric acid, urea nitrogen, creatinine were checked by BECKMAN automatic biochemical analyzer.Serum nitric oxide (NO), endothelin-1 (ET-1), adiponectin were checked by ELISA. The expression of endothelial nitric oxide synthase (eNOS) in thoracic aorta was detected by immunohistochemistry. Results:1) The level of serum uric acid, blood urea nitrogen, creatinine in model group were higher than the normal group (P<0.05), while there were no significante differences between the normal group and allopurinol treatment group (P>0.05).2) The serum level of nitric oxide, adiponectin was significantly lower (P<0.05) and endothelin-1 were markedly higher (P<0.05) in the model group than the normal group (P<0.05), while the evel of nitric oxide, adiponectin was significantly increased (P<0.05) and endothelin-1 was decreasd (P<0.05) in allopurinol treatment group compared with model group.3) Compared with the normal group, systolic blood pressure increased in model group (P<0.05). There was no increase in systolic blood pressure in allopurinol treatment group compared with the normal group (P>0.05).4) The expression of endothelial nitric oxide synthase in thoracic aorta was lower in model group than that in normal (P<0.05), it did not happen in allopurinol treatment group.5) Serum uric acid correlated with systolic blood pressure and endothelin-1 possitively, but negatively with nitric oxide and adiponectin.6) Serum adiponectin correlated with nitric oxide possitively, but negatively with systolic blood pressure and endothelin-1. Conclusion:1) 20% high yeast diet combined with potassium oxonate suspension intraperitoneal injection for 6 weeks can induce a relatively sustained chronic hyperuricemia rat model.2) Hyperuricemia induced depression of the serum level of nitric oxide and adiponectin, and leaded to the augment of the serum level of endothelin-1 and systolic blood pressure, thus, hyperuricemia concerned with blood vessel endothelium cells dysfunction intimately.3) The hypoadiponectin in hyperuriccemia rats was supposed to promote endothelial dysfunction. 4) Blood vessel endothelium cells dysfunction contribute to the development of hyertesion.5) Allopurinol was supposed to be excitomotor to upregulate the expression of eNOS, and may have a protective role to endothelial function.